Wu Shiwen, Huang Dezhao, Yu Haoliang, Tian Siyu, Malik Arif, Luo Tengfei, Xiong Guoping
Department of Mechanical Engineering, The University of Texas at Dallas, Richardson, Texas 75080, USA.
Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Phys Chem Chem Phys. 2022 May 4;24(17):10297-10304. doi: 10.1039/d1cp04510e.
Plasma-enhanced chemical vapor deposition (PECVD) provides a low-temperature, highly-efficient, and catalyst-free route to fabricate graphene materials by virtue of the unique properties of plasma. In this paper, we conduct reactive molecular dynamics simulations to theoretically study the detailed growth process of graphene by PECVD at the atomic scale. Hydrocarbon radicals with different carbon/hydrogen (C/H) ratios are employed as dissociated precursors in the plasma environment during the growth process. The simulation results show that hydrogen content in the precursors significantly affects the growth behavior and properties of graphene (, the quality of obtained graphene, which is indicated by the number of hexagonal carbon rings formed in the graphene sheets). Moreover, increasing the content of hydrogen in the precursors is shown to reduce the growth rate of carbon clusters, and prevent the formation of curved carbon structures during the growth process. The findings provide a detailed understanding of the fundamental mechanisms regarding the effects of hydrogen on the growth of graphene in a PECVD process.
等离子体增强化学气相沉积（PECVD）凭借等离子体的独特性质，为制备石墨烯材料提供了一种低温、高效且无催化剂的途径。在本文中，我们进行了反应分子动力学模拟，以在原子尺度上从理论上详细研究PECVD法制备石墨烯的生长过程。在生长过程中，具有不同碳/氢（C/H）比的烃基被用作等离子体环境中的离解前驱体。模拟结果表明，前驱体中的氢含量显著影响石墨烯的生长行为和性质（，所得石墨烯的质量，这由石墨烯片中形成的六边形碳环数量表示）。此外，结果表明增加前驱体中的氢含量会降低碳簇的生长速率，并在生长过程中防止弯曲碳结构的形成。这些发现为深入理解氢对PECVD过程中石墨烯生长影响的基本机制提供了依据。
